U.S. patent application number 11/747542 was filed with the patent office on 2008-02-07 for image forming apparatus.
Invention is credited to Kohji Hatayama, Tomofumi Inoue, Yuuji Meguro, Takeru Muramatsu, Takeshi SAKASHITA.
Application Number | 20080028967 11/747542 |
Document ID | / |
Family ID | 38933377 |
Filed Date | 2008-02-07 |
United States Patent
Application |
20080028967 |
Kind Code |
A1 |
SAKASHITA; Takeshi ; et
al. |
February 7, 2008 |
IMAGE FORMING APPARATUS
Abstract
An intermediate transfer unit includes a stand member that is
integral with an intermediate-transfer-unit body of the
intermediate transfer unit. The stand member stretches below the
intermediate-transfer-unit body from a trailing edge to a leading
edge of the intermediate-transfer-unit in an attachment direction
of the intermediate transfer unit.
Inventors: |
SAKASHITA; Takeshi; (Osaka,
JP) ; Inoue; Tomofumi; (Osaka, JP) ; Meguro;
Yuuji; (Hyogo, JP) ; Muramatsu; Takeru;
(Osaka, JP) ; Hatayama; Kohji; (Osaka,
JP) |
Correspondence
Address: |
OBLON, SPIVAK, MCCLELLAND MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Family ID: |
38933377 |
Appl. No.: |
11/747542 |
Filed: |
May 11, 2007 |
Current U.S.
Class: |
101/479 ;
101/425 |
Current CPC
Class: |
G03G 2221/1642 20130101;
G03G 21/1633 20130101; G03G 2215/00544 20130101; G03G 2215/0054
20130101; G03G 21/1638 20130101; G03G 21/168 20130101 |
Class at
Publication: |
101/479 ;
101/425 |
International
Class: |
B41F 35/00 20060101
B41F035/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 12, 2006 |
JP |
2006-162866 |
Claims
1. An image forming apparatus comprising: an apparatus body that
has two side surfaces, which are opposed to each other, and a
bottom surface; and an upper unit that can be detachably attached
to the apparatus body in a space between the two side surfaces by
movement in an attachment/detachment direction that is parallel to
the two side surfaces and the bottom surface, wherein the upper
unit includes a unit body and a unit leg that extends from the unit
body toward the bottom surface and that is positioned at least on a
portion of the unit body that is relatively interior of the
apparatus body with respect to the attachment/detachment direction,
and the upper unit is configured so that the unit body is not in
contact with the bottom surface when the upper unit is attached to
or detached from the apparatus body.
2. The image forming apparatus according to claim 1, wherein the
unit leg is configured so that a lower edge of the unit leg slides
on the bottom surface during a process of attachment or detachment
of the upper unit from the apparatus body.
3. The image forming apparatus according to claim 1, further
comprising a lower unit that can be detachably attached to the
apparatus body so as to be positioned right under the unit body and
above the bottom surface.
4. The image forming apparatus according to claim 3, wherein, when
the lower unit is attached to the apparatus body, the unit leg is
exterior to a corresponding one of two edges of the lower unit in a
direction orthogonal to the attachment/detachment direction.
5. The image forming apparatus according to claim 4, further
comprising an opening-side unit that is attached to the apparatus
body on a side, from which the upper unit is attached to and
detached from the apparatus body, after the process of attachment
or detachment of the upper unit from the apparatus body, wherein a
width of the opening-side unit along the direction orthogonal to
the attachment/detachment direction that is larger than a
corresponding width of the upper unit.
6. The image forming apparatus according to claim 5, wherein the
opening-side unit includes a recording-medium transfer unit that
transfers a toner image from a toner image carrier to a recording
medium.
7. The image forming apparatus according to claim 5, wherein the
opening-side unit includes a recording-medium conveying unit that
conveys the recording medium.
8. The image forming apparatus according to claim 4, wherein the
lower unit includes a lower-unit connecting member that is
positioned on a corresponding one of two edges of the lower unit in
the direction orthogonal to the attachment/detachment direction,
and that connects to a corresponding one of the side surfaces, and
the unit leg has any one of a through-hole and a cutout through
which the lower-unit connecting member penetrates.
9. The image forming apparatus according to claim 4, wherein the
unit leg includes a lower-unit-detachment preventing unit that
prevents the lower unit from moving in a detachment direction of
the lower unit from the apparatus body when the upper unit and the
lower unit are attached to the apparatus body.
10. The image forming apparatus according to claim 4, wherein the
upper unit is an intermediate transfer unit that includes an
intermediate transfer medium to which toner images are
primary-transferred from image carriers and from which a resultant
toner image is secondary-transferred to a recording medium.
11. The image forming apparatus according to claim 10, further
comprising a cleaning unit that cleans and collects residual toner
remaining on surfaces of the image carriers after the toner images
are primary-transferred to the intermediate transfer medium, and
residual toner remaining on a surface of the intermediate transfer
medium after the resultant toner image is secondary-transferred to
the recording medium, wherein a lower unit is a collected-toner
storage unit that stores therein the residual toner collected by
the cleaning unit.
12. The image forming apparatus according to claim 11, wherein the
cleaning unit is integral with the intermediate transfer unit and
is configured to be detachably attached to the apparatus body.
13. The image forming apparatus according to claim 4, wherein the
upper unit is a recording-medium transfer-conveying unit that
transfers toner images from image carriers to a recording medium
and conveys the recording medium.
14. The image forming apparatus according to claim 13, further
comprising a cleaning unit that cleans and collects residual toner
remaining on surfaces of the image carriers after the toner images
are primary-transferred to the intermediate transfer medium, and
residual toner remaining on a surface of the intermediate transfer
medium after the resultant toner image is secondary-transferred to
the recording medium, wherein a lower unit is a collected-toner
storage unit that stores therein the residual toner collected by
the cleaning unit.
15. The image forming apparatus according to claim 1, wherein the
upper unit further includes an upper-unit positioning member for
positioning the upper unit in the apparatus body.
16. The image forming apparatus according to claim 1, wherein the
upper unit further includes an upper-unit positioning unit for
positioning the upper unit in the apparatus body by a positioning
operation during a process of attachment of the upper unit to the
apparatus body, the upper unit moves up by the positioning
operation, and a lower edge of the unit leg is not in contact with
the bottom surface the positioning operation.
17. The image forming apparatus according to claim 1, wherein the
unit leg includes an upper-unit detachment preventing unit that
prevents the upper unit from moving in the attachment/detachment
direction, when the upper unit is attached to the apparatus
body.
18. The image forming apparatus according to claim 1, wherein the
unit leg is foldable with respect to the unit body.
19. The image forming apparatus according to claim 1, wherein the
unit leg is configured to be detachably attached to the unit
body.
20. An image forming apparatus comprising: an apparatus body that
has two side surfaces, which are opposed to each other, and a
bottom surface; and an upper unit that can be detachably attached
to the apparatus body in a space between the two side surfaces by
movement in an attachment/detachment direction that is parallel to
the two side surfaces and the bottom surface, wherein the upper
unit includes a unit body and a unit leg that extends from the unit
body toward the bottom surface, the upper unit is configured so
that the unit body is not in contact with the bottom surface when
the upper unit is attached to or detached from the apparatus body,
and the unit leg is configured so that a lower edge of the unit leg
slides on the bottom surface during a process of attachment or
detachment of the upper unit from the apparatus body.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present document incorporates by reference the entire
contents of Japanese priority document, 2006-162866 filed in Japan
on Jun. 12, 2006.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an image forming apparatus.
More specifically, the present invention relates to an image
forming apparatus that includes a unit that can be detachably
attached to a body of the image forming apparatus.
[0004] 2. Description of the Related Art
[0005] A conventional image forming apparatus of the above type is
disclosed in Japanese Patent Application Laid-open No. 2000-235309.
The conventional image forming apparatus includes an
intermediate-transfer-belt unit that can be detachably attached to
a body of the image forming apparatus (hereinafter, "image
forming-apparatus body"). A user can attach the
intermediate-transfer-belt unit to the image-forming-apparatus body
by inserting and pushing it into a space between two side walls of
the image forming-apparatus body, or can detach it by pulling it
toward the user. During the process of the attachment or
detachment, the intermediate-transfer-belt unit is not in contact
with a bottom surface of the image-forming-apparatus body. The
image forming apparatus further includes guide rails that support
the intermediate-transfer-belt unit during a process of the
attachment or detachment.
[0006] When attaching the intermediate-transfer-belt unit to the
image-forming-apparatus body, the user grips a portion on a
trailing edge (hereinafter, "trailing edge portion") of the
intermediate-transfer-belt unit in a direction in which the
intermediate-transfer-belt unit is inserted into the apparatus
body. Then, the user puts, on the guide rails, guide contact
members on a leading edge of the intermediate-transfer-belt unit in
the insertion direction of the intermediate-transfer-belt unit, and
pushes the intermediate-transfer-belt unit into the
image-forming-apparatus body along the guide rails. When detaching
the intermediate-transfer-belt unit to the image-forming-apparatus
body, the user pulls forward the intermediate-transfer-belt unit
along the guide rails, and lifts up the intermediate-transfer-belt
unit before the guide contact members come off the guide rails.
[0007] Because the guide rails support the
intermediate-transfer-belt unit during the detachment or
attachment, the intermediate-transfer-belt unit can be detached
from or attached to the image-forming-apparatus body without making
a physical contact with the bottom surface of the image forming
apparatus.
[0008] However, sometimes the user may relax the grip on the front
edge portion of the intermediate-transfer-belt unit even though the
guide contact members are not yet put on the guide rails. In such a
case, the intermediate-transfer-belt unit pivots on the trailing
edge portion that the user grips such that the leading portion of
the intermediate-transfer-belt unit falls. The leading portion may
bump against and damage, for example, the bottom surface of the
image-forming-apparatus body, or the intermediate-transfer-belt
unit itself may get damaged.
[0009] Similarly, during the detachment that the
intermediate-transfer-belt unit, the intermediate-transfer-belt
unit may pivot on the trailing edge portion that the user grips and
the trailing edge of the intermediate-transfer-belt unit fall, in
case the guide contact members come off the guide rails before the
user lifts up the intermediate-transfer-belt unit. Even in this
case, the leading edge of the intermediate-transfer-belt unit can
bump and damage, for example, the bottom surface of the
image-forming-apparatus body, or the intermediate-transfer-belt
unit itself can get damaged.
[0010] Although the intermediate-transfer-belt unit is explained
above as a unit that can be detachably attached to the
image-forming-apparatus body, any unit can have the above drawbacks
as long as the unit can be detached from or attached to the
image-forming-apparatus body while being supported by guide rails
and being not in contact with the bottom surface of the
image-forming-apparatus body.
SUMMARY OF THE INVENTION
[0011] It is an object of the present invention to at least
partially solve the problems in the conventional technology.
[0012] According to an aspect of the present invention, an image
forming apparatus includes an apparatus body that has two side
surfaces, which are opposed to each other, and a bottom surface;
and an upper unit that can be detachably attached to the apparatus
body in a space between the two side surfaces by movement in an
attachment/detachment direction that is parallel to the two side
surfaces and the bottom surface. The upper unit includes a unit
body and a unit leg that extends from the unit body toward the
bottom surface and that is positioned at least on a portion of the
unit body that is relatively interior of the apparatus body with
respect to the attachment/detachment direction, and the upper unit
is configured so that the unit body is not in contact with the
bottom surface when the upper unit is attached to or detached from
the apparatus body.
[0013] According to another aspect of the present invention, an
image forming apparatus includes an apparatus body that has two
side surfaces, which are opposed to each other, and a bottom
surface; and an upper unit that can be detachably attached to the
apparatus body in a space between the two side surfaces by movement
in an attachment/detachment direction that is parallel to the two
side surfaces and the bottom surface. The upper unit includes a
unit body and a unit leg that extends from the unit body toward the
bottom surface, the upper unit is configured so that the unit body
is not in contact with the bottom surface when the upper unit is
attached to or detached from the apparatus body, and the unit leg
is configured so that a lower edge of the unit leg slides on the
bottom surface during a process of attachment or detachment of the
upper unit from the apparatus body.
[0014] The above and other objects, features, advantages and
technical and industrial significance of this invention will be
better understood by reading the following detailed description of
presently preferred embodiments of the invention, when considered
in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a schematic side view of a printer according to an
embodiment of the present invention;
[0016] FIG. 2 is a schematic side view of the printer with an
exterior front cover open;
[0017] FIG. 3 is a schematic front view of the printer with the
exterior front cover open;
[0018] FIGS. 4A and 4B are schematic perspective views of the
printer for explaining an operation for removing out each unit from
the inside of the printer;
[0019] FIG. 5 is a perspective view of an intermediate transfer
unit and a collected-toner box;
[0020] FIG. 6 is an enlarged left side view of the intermediate
transfer unit and the collected-toner box;
[0021] FIG. 7 is an enlarged right side view of the intermediate
transfer unit and the collected-toner box;
[0022] FIG. 8A is a perspective cut-away view of a printer
body;
[0023] FIG. 8B is a schematic perspective view of the intermediate
transfer unit;
[0024] FIG. 9A is a schematic side view of the printer, depicting
the state before positioning of the intermediate transfer unit;
[0025] FIG. 9B is a schematic side view of the printer, depicting
the state after positioning of the intermediate transfer unit;
[0026] FIG. 10 is a schematic upper view of the printer for
explaining a locking mechanism;
[0027] FIG. 11 is a schematic front view of a modification of the
printer with an exterior front cover open;
[0028] FIG. 12 is a schematic side view of a printer according to a
second embodiment of the present invention;
[0029] FIG. 13 is a schematic side view of the printer shown in
FIG. 12 with the exterior front cover open; and
[0030] FIG. 14 is a schematic front view of the printer shown in
FIG. 12 with the exterior front cover.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0031] Exemplary embodiments of the present invention are explained
in detail below with reference to the accompanying drawings.
[0032] FIG. 1 is a schematic side view of a printer 100 according
to an embodiment of the present invention. The printer 100 is a
full color printer. The printer 100 is an example of an
image-forming apparatus.
[0033] The printer 100 includes an intermediate transfer unit 80
almost at the center in an image-forming-apparatus body. The
intermediate transfer unit 80 includes an intermediate transfer
belt 8a that is wound around and extends across a plurality of
rollers. Along an upper surface of the intermediate transfer belt
8a, four image forming units 4 (4K, 4C, 4M, and 4Y) are arranged.
Above the image forming units 4 is arranged an exposure unit 3 that
applies each light beam to each photoreceptor of each of the image
forming units 4K, 4C, 4M, and 4Y. Below the image transfer unit
body is arranged a collected-toner box 14 for storing residual
toner residing on the intermediate transfer belt 8a and residing on
the surfaces of the photoreceptors after the residual toner is
removed and collected. Below the collected-toner box 14,
furthermore, a sheet cassette 1 is arranged.
[0034] On the right of the intermediate transfer unit 80 shown in
FIG. 1, a secondary transfer unit 11a that includes a secondary
transfer roller 11 is provided. Above the secondary transfer roller
11, a fixing unit 12 is arranged. The intermediate transfer belt 8a
has a portion that is opposed to the secondary transfer roller 11
and that is supported by a transfer opposed roller 10. The portion
serves as a secondary transfer point.
[0035] A full color image is formed in the following manner. The
exposure unit 3 applies a light beam to each of the surfaces of the
photoreceptors of the image forming units 4K, 4C, 4M, and 4Y so
that color toner images are formed on the surfaces of the
photoreceptors. The color toner images are primary-transferred to
the intermediate transfer belt 8a at primary transfer points where
the photoreceptors and the intermediate transfer belt 8a are
opposed. Accordingly, a layered color-toner image is formed on the
surface of the intermediate transfer belt 8a.
[0036] Transfer sheets stacked on the sheet cassette 1 are fed by a
feeding roller 2 one by one and reach resist rollers 9. The resist
rollers 9 conveys the transfer sheet at a timing when the layered
color-toner image on the intermediate transfer belt 8a reaches the
secondary transfer point, and the layered color-toner image is
transferred to the transfer sheet at the secondary transfer
point.
[0037] The layered color-toner image on the transfer sheet is fixed
by the fixing unit 12 and then discharged by discharging rollers
17. Residual toner residing on the intermediate transfer belt 8a is
removed by a cleaning unit 13, using a cleaning mechanism, and
stored in the collected-toner box 14. The collected-toner box 14
can be configured to store residual toner collected from the
surfaces of the photoreceptors of the image forming units 4.
[0038] A user stands on the side of an arrow X shown in FIG. 1
(hereinafter, "front side") and performs operations including
maintenance work of the printer 100 and replacement work of
consumed parts.
[0039] FIG. 2 is a schematic side view of the printer 100, whose
exterior front cover 5 is open, for explaining directions in which
the units of the printer 100 are detached from a printer body of
the printer 100 (hereinafter, "detachment direction"). The exterior
front cover 5 is caused to pivot on an exterior-front-cover pivot
shaft 27 to open in the direction indicated by the arrow X shown in
FIG. 1. Accordingly, the secondary transfer unit 11a, the
intermediate transfer unit 80, and the collected-toner box 14 can
be detached from the printer body respectively in the directions
indicated by arrows A, B, and C shown in FIG. 2. An exterior upper
cover 6 is caused to pivot and open in the direction indicated by
an arrow D shown in FIG. 2 to detach the image forming units 4K,
4C, 4M, and 4Y from the printer body in the directions indicated by
arrows E shown in FIG. 2.
[0040] If the printer is small-sized, layout of the units is
required to assure space for each of the units and not to cause
interference among the units during detachment or attachment of the
units.
[0041] FIG. 3 is a schematic front view of the printer 100, viewed
from the side of the arrow X shown in FIG. 2, whose exterior front
cover 5 is open. The units that can be detachably attached to the
printer 100 are attached to the printer 100 so as to be seen from a
certain side at a time. Accordingly, all of the units can be
detached in the directions indicated by the arrow X shown in FIG.
2.
[0042] As shown in FIG. 3, the intermediate transfer unit 80 is
attached to the printer 100 such that the intermediate transfer
unit 80 is housed in a unit attachment space 50 defined by two side
plates 110 serving as side surfaces, a bottom plate 101 serving as
a bottom surface, and the exterior upper cover 6. When the exterior
front cover 5 opens, a boundary between the unit attachment space
50 and the outside of the printer 100 serves as an opening. As
shown in FIG. 3, the intermediate transfer unit 80 is attached to
the printer 100 so as not to be in contact with the bottom plate
101 and positioned above the collected-toner box 14. The
intermediate transfer unit 80 serves as an upper unit and the
collected-toner box 14 serves as a lower unit. An
intermediate-transfer-unit body 8 of the intermediate transfer unit
80 includes the intermediate transfer belt 8a that is positioned
above the bottom plate 101 and that is not in contact with the
collected-toner box 14. The intermediate transfer unit 80 includes
two stand members 81 each serving as a unit leg. Each of the stand
members 81 is on each of the two edges of the
intermediate-transfer-unit body 8 in a unit width direction (the
direction indicated by an arrow Y shown in FIG. 3) and extends from
the intermediate-transfer-unit body toward the bottom plate 101.
When the intermediate transfer unit 80 and the collected-toner box
14 are attached to the printer 100, each of the stand members 81 is
positioned exterior of each of the edges of the collected-toner box
14 in the unit width direction as shown in FIG. 3, and the
intermediate transfer unit 80 crosses the collected-toner box
14.
[0043] As against the printer 100, the conventional image forming
apparatus includes guide rails that support the two side edges of
the intermediate transfer unit 80 to guide the intermediate
transfer unit 80, and that are positioned in an upper portion of
the printer body. To attach the intermediate transfer unit 80 to
the conventional image forming apparatus, a user grips a portion on
the trailing edge portion of the intermediate transfer unit 80 in
the attachment direction, and lifts up a leading edge of the
intermediate transfer unit 80 in the attachment direction. After
knowing that the leading edge is put on the guide rails, the user
relaxes the grip on the trailing edge portion and pushes the
intermediate transfer unit 80 into the apparatus body while
gripping the trailing edge portion. In this manner, the
intermediate transfer unit 80 is attached to the conventional image
forming apparatus. However, sometime, although the leading edge is
not yet put on the guide rails, the user relaxes the grip so that
the intermediate transfer unit 80 pivots on the trailing edge
portion that the user grips and the leading edge falls. As a
result, the intermediate-transfer-unit body 8 bumps against, for
example, the bottom plate 101 so that the intermediate transfer
unit 80 is damaged.
[0044] Similarly, sometimes, the intermediate transfer unit 80 is
damaged in the process of detaching the intermediate transfer unit
80 from the conventional image forming apparatus. This happens in
case the user fails to grip the trailing edge portion firmly to
lift up the leading edge at the timing when the leading edge comes
off the guide rails, and thus, the intermediate transfer unit 80
pivots on the trailing edge portion that the user grips and the
leading edge falls so that the intermediate transfer unit 80 bumps
against, for example, the bottom plate 101.
[0045] On the other hand, as shown in FIG. 3, the printer 100
according to the first embodiment includes the stand members 81
that are integral with the intermediate-transfer-unit body. Each of
the stand members 81 stretches below the intermediate-transfer-unit
body 8 from the leading edge to the trailing edge of the
intermediate-transfer-unit body 8 along the attachment direction as
shown in FIG. 4 that is explained below. In other words, the stand
members 81 are positioned also on the leading edge of the
intermediate-transfer-unit body 8 in the attachment direction.
Accordingly, when the intermediate transfer unit 80 is to pivot on
the trailing edge portion gripped by the user in a process of
attachment or detachment of the intermediate transfer unit 80,
leading edges of the stand members 81 in the attachment direction
prevents pivoting of the intermediate transfer unit 80. In this
manner, the leading edge of the intermediate transfer unit 80 can
be prevented from falling and bumping against, for example, the
bottom plate 101.
[0046] Furthermore, the lower edge of each of the stand members 81
of the printer 100 is in contact with the bottom plate 101 during
the detachment/attachment process. Hence, by sliding the
intermediate transfer unit 80 while the lower edges of the stand
members 81 are in contact with the bottom plate 101, the
intermediate transfer unit 80 can be detached from and attached to
the printer body. Accordingly, the leading edge of the intermediate
transfer unit 80 can be prevented from falling and damaging, for
example, the bottom plate 101 when the user fails to grip properly
the trailing edge portion of the intermediate transfer unit 80.
[0047] Because the stand members 81 are provided to the two edges
of the intermediate-transfer-unit body in the unit width direction,
the lower edges of the stand members 81 can be kept being in
contact with the bottom plate 101 without a force to be vertically
applied to the intermediary transfer unit 80. Accordingly, by
applying only a force in the attachment/detachment direction for
sliding the intermediate transfer unit 80, the intermediate
transfer unit 80 can be attached to and detached from the printer
body.
[0048] FIGS. 4A and 4B are schematic perspective views of the
printer 100 for explaining an operation for detaching the
intermediate transfer unit 80 and the secondary transfer unit 11a
from the printer body. FIG. 4A depicts the state where the exterior
front cover 5 is open, and FIG. 4B depicts the state after the
intermediate transfer unit 80 is removed out by pulling forward
from the printer body.
[0049] To pull the intermediate transfer unit 80 from the printer
body in the direction indicated by an arrow X shown in FIG. 4A, the
exterior front cover 5 opens in a direction indicated by an arrow
shown in FIG. 4A. The intermediate transfer unit 80 needs to be
moved from a position more interior in the printer body than a
space F is where the secondary transfer unit 11a is positioned when
the exterior front cover 5 is closed. The secondary transfer unit
11a serves as an opening-side unit. The width M of the secondary
transfer unit 11a shown in FIG. 4A is longer than the width m of
the intermediate transfer unit 80 as shown in FIG. 4A.
[0050] In an image forming apparatus that includes guide rails
arranged in the apparatus body, if the width of the secondary
transfer unit is equal to or larger than the width of the
intermediate transfer unit, the guide rails cannot be positioned in
the space F shown in FIG. 4A for the secondary transfer unit 11a.
In other words, the guide rails are positioned in a portion more
interior of the apparatus body than a portion is that extends as
indicated by an arrow L shown in FIG. 4A, and cannot extend to the
opening that is the boundary between the unit attachment space 50
and the outside of the printer 100. This makes it difficult for the
user to know the timing when portions of the intermediate transfer
unit 80 that are supported by the guide rails come off the guide
rails. If the user fails to know the timing properly, the supported
portions come off and fall. Accordingly, the intermediate transfer
unit 80 may fall and bump against, for example, the bottom plate
101 and the intermediate transfer unit 80 may be damaged in the
worst case. Because the edges of the guide rails that face the
opening are positioned in the apparatus body at relatively the rear
side of the printer body, the user cannot see easily the position
of the guide rails. Also because of the position of the guide
rails, the intermediate transfer unit 80 may bump against other
members of the image forming apparatus so that the intermediate
transfer unit 80 and other members may get damaged.
[0051] On the other hand, as shown in FIG. 4B, the printer 100
includes the stand members 81 that are integral with the
intermediate-transfer-unit body 8, and the stand members 81 support
the intermediate-transfer-unit body 8 even after the intermediate
transfer unit 80 is removed out of the printer body. Accordingly,
the intermediate transfer unit 80 can be detached and attached to
the printer 100 properly not as in the case of the image forming
apparatus described above where the space for the secondary
transfer unit 11a causes the above inconvenience. Note that the
cleaning unit 13 is fixed to the intermediate transfer unit 80 and
can be attached to and detached from the printer body along with
the intermediate transfer unit 80.
[0052] To detach the intermediate transfer unit 80, the
collected-toner box 14, and the secondary transfer unit 11a from
the printer 100, the exterior front cover 5 opens as shown in FIGS.
2 and 4A. When the exterior front cover 5 opens, the secondary
transfer unit 11a originally fixed to the exterior front cover 5 is
pulled forward from the printer body as shown in FIG. 4A.
Thereafter, the secondary transfer unit 11a is detached from the
exterior front cover 5. Subsequently, the collected-toner box 14
originally positioned below the intermediate transfer unit 80 is
detached from the printer body while being horizontally pulled
forward in the direction indicated by the arrow C shown in FIG. 2.
The intermediate transfer unit 80 is then horizontally pulled
forward from the printer body in the direction indicated by the
arrow B shown in FIG. 2 as shown in FIG. 4B, and detached from the
printer body. The stand members 81 serve as guide members during
the detachment/attachment process.
[0053] FIG. 5 is a perspective view of the intermediate transfer
unit 80 and the collected-toner box 14 that are attached to the
printer 100 and that are viewed from approximately from the front
side (the side of the arrow X shown in FIG. 1). FIG. 6 is an
enlarged left side view of front portions of the intermediate
transfer unit 80 and the collected-toner box 14 in FIG. 5.
[0054] To position the collected-toner box 14 on the side plates
110, a positioning pin 141 needs to be pulled out of the
collected-toner box 14. However, as shown in FIG. 3, each of the
stand members 81 in the printer body is exterior of each of the
edges of the collected-toner box 14 in the unit width direction,
thus interrupting the positioning of the collected-toner box 14. To
prevent such interruption, a cutout 81a is formed in the stand
member 81 as shown in FIG. 6.
[0055] Instead of the positioning pin 141 provided to the collected
toner box 14, a hole for positioning the collected-toner box 14 can
be provided in the collected-toner box 14 and the positioning pin
141 can be provided to the side plates 110. However, the
positioning pin 141 that is laid across the collected-toner box 14
and the printer body is laid on the path, through which the stand
member 81 is pulled forward, and interrupts the intermediate
transfer unit 80 from being pulled forward along the path. To allow
the intermediate transfer unit 80 to be pulled forward, the printer
100 has a space having a width F shown in FIG. 5 that is larger
than the width of the stand member 81, and the positioning pin 141
is laid across the space when the collected-toner box 14 is
attached to the printer 100. With the above structure, the stand
member 81 can be pulled forward along with the
intermediate-transfer-unit body 8 after the collected-toner box 14
is pulled forward from the printer body.
[0056] FIG. 7 is an enlarged right side view of the front portions
of the intermediate transfer unit 80 and the collected-toner box 14
in FIG. 5. The residual toner residing on the intermediate transfer
belt 8a is removed by the cleaning unit 13, and then, it is
conveyed to the collected-toner box 14 through a collection duct
13a and an introducing portion 14a. Because the cleaning unit 13 is
positioned above the intermediate transfer unit 80 and the
collected-toner box 14 is positioned below the intermediate
transfer unit 80, a duct cutout 81b is provided to the stand member
81 to connect the cleaning unit 13 and the colleted-toner box 14,
which would otherwise be not connected because of the stand member
81. Accordingly, the cleaning unit 13 and the collected-toner box
14 can be connected with the collection duct 13a. The body of the
collected-toner box 14 is block-shaped in conformity with the shape
of the printer 100 and has the most compact shape. However, the
collection duct 13a needs to connect the cleaning unit 13 and the
collected-toner box 14 so as not to overlap the intermediate
transfer unit 80 positioned between the cleaning unit 13 and the
collected-toner box 14. For this reason, the introducing portion
14a juts out of the block-shaped body of the collected-toner box 14
as shown in FIGS. 5 and 7.
[0057] Because the collection duct 13a that serves as a toner
conveying path is closer to a position where the collection duct
13a is vertical, the toner falls into the collected-toner box 14 by
gravity. More specifically, as shown in FIG. 7, the collection duct
13a is in a position where an angle 0 formed by the vertical axis
and the collection duct 13a is not larger than 45.degree.. In other
words, by setting an angle, at which the toner is flown through the
collection duct 13a, to the horizontal plane to an angle not
smaller than 45.degree. and not larger than 90.degree., the toner
can fall into the collected-toner box 14 by gravity with the simple
structure of the collection duct 13a.
[0058] The processes involved in setting the intermediate transfer
unit 80 on the printer body will be explained below. FIG. 8A is a
perspective cut-away view of the printer 100, and FIG. 8B is a
schematic perspective view of the intermediate transfer unit
80.
[0059] As shown in FIG. 8B, the intermediate transfer unit 80
includes main reference portions 85 that serve as upper-unit
positioning members, and sub reference portions 86 that serve as
upper-unit positioning members. The main reference portions 85 are
on the two edges of the transfer opposed roller 10 in the unit
width direction, the transfer opposed roller 10 being on the
trailing edge of the intermediate transfer unit 80 in the
attachment direction. The sub reference portions 86 are on the
leading edge of the intermediate transfer unit in the attachment
direction.
[0060] As shown in FIG. 8A, each of the side plates 110 has a
main-reference-portion receiving portion 82a for positioning the
main reference portion 85 on the printer body, and a
sub-reference-portion receiving portion 83a for positioning the sub
reference portion 86 on the printer body.
[0061] By sliding the intermediate transfer unit 80 on the bottom
plate 101, the intermediate transfer unit 80 is attached to the
printer 100 in the direction indicated by an arrow G shown in FIGS.
8A and 8B.
[0062] FIG. 9A is a schematic side view of the printer 100,
depicting the state before positioning the intermediate transfer
unit 80 on the printer body, and FIG. 9B is a schematic side view
of the printer 100, depicting the state after positioning the
intermediate transfer unit 80 on the printer body.
[0063] As shown in FIG. 9A, when the intermediate transfer unit 80
slides on the bottom plate 101 in the direction, which is indicated
by the arrow G shown in FIG. 8A, the lower edges of the stand
members 81 are in contact with the bottom plate 101. The main
reference portions 85 passes through main-reference-portion sliding
portions 82b at the front of the main-reference-portion receiving
portions 82a, and the sub reference portions 86 pass through
sub-reference-portion sliding portions 83b at the front of the
sub-reference-portion receiving portions 83a. When the intermediate
transfer unit 80 shown in FIG. 9A is further pushed into the
printer body, the main reference portions 85 lift up respectively
along rear sloping surfaces of the main-reference-portion sliding
portions 82b, and reach the main-reference-portion receiving
portions 82a and bumps against the rear surfaces of the
main-reference-portion receiving portions 82a. Meanwhile, the sub
reference portions 86 lift up respectively along rear sloping
surfaces of the sub-reference-portion sliding portions 83b, and
reach the sub-reference-portion receiving portions 83a and bumps
against the rear surfaces of the sub-reference-portion receiving
portions 83a. In this manner, the main reference portions 85 and
the sub reference portions 86 are positioned in the printer 100 as
shown in FIG. 9B.
[0064] After the positioning, the lower edges of the stand members
81 are not in contact with the bottom plate 101 because the main
reference portions 85 and the sub reference portions 86 lift up
during the positioning.
[0065] Because improper positioning of the intermediate transfer
unit 80 on the printer body leads to deterioration in image
quality, accurate positioning of the intermediate transfer unit 80
is required. If the stand members 81 are positioned on the printer
body instead of the main reference portions 85 and the sub
reference portions 86, the stand members 81 need to be manufactured
with high accuracy and attached to the intermediate-transfer-unit
body with high accuracy. This results in the cost increase. On the
other hand, in the case where the main reference portions 85 and
the sub reference members 86 are provided as described above for
the positioning of the intermediate transfer unit 80 on the printer
body, the accuracy in manufacturing and attachment of the stand
members 81, which would otherwise be required, can be lowered.
[0066] As described, the stand members 81 assist in the attachment
or detachment of the intermediate transfer unit 80. After the
positioning, the stand members 81 are not in contact with the
bottom plate 101 as shown in FIG. 9B. In other words, the
intermediate transfer unit 80 does not vertically interrupt the
main reference portion 85 and the sub reference portions 86.
[0067] Explanation is given below about a locking unit serving as
an upper-unit detachment preventing unit that prevents the
intermediate transfer unit 80 being attached to the printer 100
from moving in the detachment direction.
[0068] FIG. 10 is a schematic upper view of the printer 100 for
explaining the locking unit. As shown in FIG. 10, each of the stand
members 81 includes an exterior leaf spring 87 that faces a
corresponding one of the side plates 110, and each of the side
plates 110 includes a side-plate recess portion 87a in which the
exterior leaf spring 87 fits. When the intermediate transfer unit
80 is inserted into the printer body to position the intermediate
transfer unit 80 as shown in FIG. 9B, the exterior leaf springs 87
fit respectively in the side-plate recess portions 87a.
Accordingly, the intermediate transfer unit 80 is locked on the
side plates 110. Hence, the intermediate transfer unit 80 can be
prevented from moving in the detachment direction indicated by the
arrow X shown in FIG. 10.
[0069] Note that the intermediate transfer unit 80 is unlocked
easily from the side plates 110 by pulling forward the intermediate
transfer unit 80 from the printer body.
[0070] In addition, each of the stand members 81 includes an
interior leaf spring 88 that faces the collected-toner box 14, and
the collected-toner box 14 includes recess portions 88a in each of
which a corresponding one of the interior leaf springs 88 fits.
Each of the recess portions 88a is positioned on each of the two
edges of the collected-toner box 14 in the unit width direction.
When the collected-toner box 14 is inserted into the printer body
after the positioning of the intermediate transfer unit 80, each of
the interior leaf springs 88 fits in each of the recess portions
88a and the collected-toner box 14 is positioned below the
intermediate transfer unit 80. Accordingly, the collected-toner box
14 is locked on the intermediate transfer unit 80. Because the
intermediate transfer unit 80 is locked in the printer body,
collected-toner box 14 can be prevented from moving in the
detachment direction indicated by the arrow X shown in FIG. 10.
[0071] Note that the collected-toner box 14 is unlocked easily from
the intermediate transfer unit 80 by pulling forward the
collected-toner box 14.
[0072] The locking unit is not limited to the exterior leaf springs
87 and the interior leaf springs 88. For example, if the stand
members 81 are made of resin, a snap-fit shape can be provided to
each of the stand members 81 instead of the interior leaf springs
88 to lock the intermediate transfer unit 80 on the collected-toner
box 14.
[0073] The stand members 81 are detachably attached to the
intermediate-transfer-unit body 8. Hence, only the
intermediate-transfer-unit body 8 in a small volume can be
transferred. Alternatively, the stand member 81 can be configured
to be foldable such that the intermediate transfer unit 80 can be
small in volume when transferred.
[0074] In the first embodiment is explained the intermediate
transfer unit 80 including the stand members 81 that serve as unit
legs and that are positioned on the two edges of the
intermediate-transfer-unit body 8 in the unit width direction.
Alternatively, the intermediate transfer unit 80 can be configured
to include a single stand member provided any one of the two edges
of the intermediate-transfer-unit body in the unit width direction,
and a guided member provided to the other edge and configured to
slide on a guide rail provided in the printer body.
[0075] FIG. 11 is a schematic front view of a modification of the
printer 100 whose exterior front cover 5 is open.
[0076] As shown in FIG. 11, the intermediate transfer unit 80
includes the stand member 81 on a right one of the two edges of the
intermediate-transfer-unit body 8 in the unit width direction in
FIG. 11, and a guided member 91 provided on the other left edge and
supported by a guide rail 92 provided to the side plate 110 on the
left in FIG. 11.
[0077] The modification shown in FIG. 11 can have the same
structure of the intermediate transfer unit 80 of the first
embodiment, excluding the stand member 81 on the right edge and the
guided member 91 on the left edge.
[0078] The fall of the intermediate transfer unit 80 during the
attachment or detachment occurs in a manner that the intermediate
transfer unit 80 pivots on the trailing edge portion that the user
grips and the leading edge of the intermediate transfer unit 80
falls while the user is supporting the trailing edge portion. To
prevent the fall of the intermediate transfer unit 80, the stand
member 81 is provided on one of the two edges of the
intermediate-transfer-unit body 8 in the unit width direction. The
stand member 81 prevents the pivoting of the intermediate transfer
unit 80, thus preventing the leading edge of the intermediate
transfer unit 80 from falling.
[0079] Because the stand member 81 has a surface at a level
equivalent to that of the guide rail 92, the guided member 91 is
put on the guide rail 92 by only sliding the stand member 81 such
that the lower edge of the stand member 81 is in contact with the
bottom plate 101. With the above structure, the user needs not to
see where the guide rail is to insert or pull forward the
intermediate transfer unit 80 from the printer body. Accordingly,
the intermediate transfer unit 80 and other units can be prevented
from being damaged during the inserting or pulling out of the
intermediate transfer unit 80 from the printer body.
[0080] Because the stand member 81 is provided on the only one of
the two edges of the intermediate transfer unit 80 in the unit
width direction, the intermediate transfer unit in the modification
interrupts only one of the edges of the collected-toner box 14 in
the unit width direction. In other words, the edge of the
collected-toner box 14 on which the guide rail 92 is provided is
not interrupted by the stand member 81, and the printer body and
the collected-toner box 14 can be connected easily.
[0081] In the first embodiment and its modification explained
above, the intermediate transfer unit 80 serves as an upper unit
that includes at least one stand member. In a second embodiment of
the present invention described below, a transfer-conveying unit
serves as the upper unit.
[0082] FIG. 12 is a schematic side view of a printer 200 according
to the second embodiment. The printer 200 includes a transfer
conveying unit 70 that includes a transfer-conveying belt 7a that
is wound around and extends across a plurality of rollers and that
is positioned at approximately the center of a printer body of the
printer 200. Along an upper surface of the transfer-conveying belt
7a, the image forming units 4 (4K, 4C, 4M, and 4Y) each include a
photoreceptor are arranged. Above the image forming units 4, the
exposure unit 3 that applies a light beam to each of the
photoreceptors is arranged. On the inner surface of the
transfer-conveying belt 7a, four transfer rollers 21 (21K, 21C,
21M, and 21Y) are provided in portions that face respectively the
photoreceptors.
[0083] Below a transfer-conveying-unit body 7 is provided the
collected-toner box 14 for storing residual toner on the
transfer-conveying belt 7a and on the surfaces of the
photoreceptors after the residual toner is removed and collected.
Below the collected-toner box 14, the sheet cassette 1 is
arranged.
[0084] A full color image is formed in the printer 200 in the
following manner. The exposure unit 3 applies each light beam to
each of the photoreceptors of the image forming units 4 so that
each color toner image is formed on each of the surfaces of the
photoreceptors.
[0085] Transfer sheets stacked on the sheet cassette 1 are fed by
the feeding roller 2 one by one and then reach the resist rollers
9. The transfer sheet is fed by the resist rollers 9 at a timing
such that the color toner images on the surfaces of the
photoreceptors are transferred to the transfer sheet on the
transfer-conveying belt 7a at transfer positions that faces the
transfer rollers 21K, 21C, 21M and 21Y. Accordingly, a layered
color toner image is formed on the surface of the transfer sheet.
During the transfer, the transfer sheet is conveyed on and by the
transfer-conveying belt 7a.
[0086] The transfer sheet having the layered color toner image
thereon is conveyed on the transfer-conveying belt 7a to the fixing
unit 12 to fix the layered color toner image. After the layered
color toner image is fixed as an image on the surface of the
transfer sheet, the transfer sheet is discharged to a
discharged-sheet tray 120. Residual toner removed from the
transfer-conveying belt 7a and the surfaces of the photoreceptors
is stored in the collected-toner box 14.
[0087] As in the case of the printer 100, a user stands on the side
of an arrow X shown in FIG. 12 (hereinafter, "front side") and
performs operations, maintenance work of the printer 200, and
replacement of consumed parts.
[0088] FIG. 13 is a schematic side view of the printer 200 whose
exterior front cover 5 is open, for explaining directions in which
the units of the printer 200 are detached. The exterior front cover
5 is caused to pivot on the exterior-front-cover pivot shaft 27 to
be opened in the direction indicated by the arrow X shown in FIG.
13. Accordingly, the transfer conveying unit and the
collected-toner box 14 can be detached from the printer body
respectively in the directions indicated by arrows B and C shown in
FIG. 13.
[0089] FIG. 14 is a schematic front view of the printer 200 whose
exterior front cover 5 is open, viewed from the front side. The
units of the printer 200 are arranged so as to be seen from a
certain direction at a time. This means that all the units can be
detached from or attached to the printer body in the direction
indicated by the arrow X shown in FIG. 13.
[0090] The printer 200 shown in FIG. 14 includes the transfer
conveying unit 70 that is positioned at almost the center of the
printer 200. On the contrary, the printer 100 shown in FIG. 3
includes the intermediate transfer unit 80 that is positioned at
almost the center of the printer 100 and that includes the cleaning
unit 13. Other units of the printer 200 are arranged as in the
printer 100, and thus, the transfer conveying unit 70 can be
detached from and attached to the printer body with the same
structure as that of the intermediate transfer unit 80. Such a
structure prevents a leading edge of the transfer conveying unit 70
in a direction, in which the transfer conveying unit 70 is attached
to the printer body, from falling and bumping against, for example,
the bottom plate 101, thereby preventing damage of the transfer
conveying unit 70 during its detachment or attachment.
[0091] As shown in FIGS. 12 and 13, the printer 200 includes the
exterior front cover 5 on the right in FIGS. 12 and 13 and the
fixing unit 12 on the left side. In addition, the exterior front
cover 5 includes a transfer-conveying path that extends from the
sheet cassette 1 to the transfer conveying unit 70.
[0092] Alternatively, the fixing unit 12 can be provided to the
exterior front cover 5 (on the right in FIG. 12) and the
transfer-conveying path can be positioned in the apparatus body on
a rear side (on the left in FIG. 12) opposite to the front side
such that the transfer conveying unit 70 is positioned between the
transfer path and the exterior front cover 5. With the structure,
the transfer sheet is fed to the transfer conveying unit 70 and
conveyed by and on the transfer-conveying belt 7a from the rear
side to the front side. Because the fixing unit 12 is provided to
the exterior front cover 5, all of the units inside the printer 200
can be seen in the single direction when the exterior front cover 5
opens.
[0093] As described, the printer 200 includes the stand members 81
that are integral with the intermediate-transfer-unit body 8. Each
of the stand members 81 stretches below the transfer-conveying-unit
body 7 from the leading edge to the trailing edge of the
transfer-conveying-unit body 7 along the attachment direction. In
other words, the stand members 81 are positioned also on the
leading edge of the transfer-conveying-unit body in the attachment
direction. Accordingly, when the transfer conveying unit 70 is to
pivot on the trailing edge portion that the user grips in the
process of attachment or detachment of the transfer conveying unit
70, the leading edges of the stand members 81 in the attachment
direction prevents the pivoting of the transfer conveying unit 70.
Hence, the leading edge portion of the transfer conveying unit 70
in the attachment direction can be prevented from falling and
bumping against, for example, the bottom plate 101.
[0094] In the printer 100, the lower edges of the stand members 81
are in contact with the bottom plate 101 during the attachment or
detachment. Hence, by sliding the intermediate transfer unit 80 on
the bottom plate 101 while the lower edges of the stand members 81
are in contact with the bottom plate 101, the intermediate transfer
unit 80 can be detached from and attached to the printer body.
Accordingly, the leading edge of the intermediate transfer unit 80
can be prevented from falling and damaging, for example, the bottom
plate 101 when the user fails to grip properly the trailing edge
portion of the intermediate transfer unit 80 in the
detachment/attachment direction.
[0095] Because the intermediate transfer unit 80 includes the stand
members 81 on the two edges of the intermediate transfer-unit body
in the unit width direction, the lower edges of the stand members
81 can be kept being in contact with the bottom plate 101 without a
force to be vertically applied to the intermediate transfer unit
80. Accordingly, by only applying a force to slide the intermediate
transfer unit 80 on the bottom plate 101, the intermediate transfer
unit 80 can be attached to and detached from the printer body.
Thus, the detachment/attachment characteristics of the intermediate
transfer unit 80 can be improved, especially because the
intermediate transfer unit 80 is configured to slide to a position
above the opened exterior front cover 5 as shown in FIG. 4B.
[0096] In addition, the intermediate-transfer-unit body 8 is not in
contact with the bottom plate 101 during the process of attachment
or detachment. In addition, the intermediate-transfer-unit body is
not in contact with the bottom plate 101 while being attached to or
detached from the printer body. Hence, the collected-toner box 14
can be provided as the lower unit right below the
intermediate-transfer-unit body 8 and above the bottom plate
101.
[0097] The intermediate-transfer-unit body 8, the collected-toner
box 14, and the stand members 81 are arranged such that, as shown
in FIG. 3, the stand members 81 are exterior of the two edges of
the collected-toner box 14 in the unit width direction when the
intermediate transfer unit 80 and the collected-toner box 14 are
attached to the printer 100. Accordingly, the
intermediate-transfer-unit body, the collected-toner box 14, and
the stand members 81 can be attached to or detached from the
printer body in the single direction.
[0098] The printer 100 includes the secondary transfer unit 11a
that serves as the opening-side unit and that includes a
recording-medium transfer unit and a recording-medium conveying
unit. After the attachment of the intermediate transfer unit 80,
the secondary transfer unit 11a is attached to the printer 100 on
the front side. The width M of the secondary transfer unit 11a is
equivalent to or larger than the width m of the intermediate
transfer unit 80. If the guide rails are provided for the
intermediate transfer unit 80 as in the printer 100, the guide rail
cannot extend in the printer body to the space where the secondary
transfer unit 11a is positioned when the exterior front cover 5 is
closed. With this structure, the user needs to see where the guide
rails are for the detachment and attachment of the intermediate
transfer unit 80. Hence, the intermediate transfer unit 80 may
sometime bump against other members of the printer 100 and the
intermediate transfer unit 80 and other members of the printer 100
may get damaged. With the structure of the first embodiment, on the
other hand, the stand members 81 are in contact with the bottom
plate 101 while the intermediate transfer unit 80 slides on the
bottom plate 101 to be attached to or detached to the printer body.
Accordingly, the user needs not to see where the guide rails are
even though the unit having the larger width than that of the
intermediate transfer unit 80 is provided to the printer 100 on the
front side. Hence, the damage of the intermediate transfer unit 80
and other members of the printer 100 can be prevented, which would
otherwise occur by repetition of the inserting and pulling forward
of the intermediate transfer unit 80 from the printer body.
[0099] In addition, because the secondary transfer unit 11a serves
as the opening-side unit including the recording-medium transfer
unit and the receding-medium conveying unit, the detachment or
attachment of the recording-medium transfer unit and the
receding-medium conveying unit is easy. Hence, the maintenance work
for the recording-medium transfer unit and the receding-medium
conveying unit are easy.
[0100] The collected-toner box 14 includes the positioning pin 141
that serves as a lower-unit connecting member that connects to the
side plate 110 on a corresponding one of the edges of the
collected-toner box 14 in the unit width direction, and a
corresponding one of the stand members 81 has the cutout 81a
through which the positioning pin 141 penetrates. Because of the
cutout 81a, the stand member 81 does not occupy the space between
the collected-toner box 14 and the side plate 110, and the
collected-toner box 14 can be positioned on the printer body.
[0101] The stand members 81 each include the interior leaf spring
88 as the lower-unit detachment preventing unit to prevent the
collected-toner box 14 from moving in the detachment direction when
the intermediate transfer unit 80 and the collected-toner box 14
are attached to the printed body. Hence, the collected-toner box 14
can be prevented from falling off. In addition, since the stand
members 81 that are close to the collected-toner box 14 include the
locking unit, the structure of the lower-unit-detachment preventing
unit can be simplified.
[0102] Because the intermediate transfer unit 80 serves as the
upper unit, the detachment or attachment of the intermediate
transfer unit 80 is possible without damaging the intermediate
transfer belt 8a.
[0103] Because the collected-toner box 14 serves as the
collected-toner storage unit and the lower unit, the collected
toner can be removed out of the printer 100 easily.
[0104] The cleaning unit 13 serving as the cleaning unit can be
detachably attached to the printer body along with the intermediate
transfer unit 80. Hence, it suffices that the cleaning unit 13 be
fixed to the intermediate transfer unit 80, and other structure for
attachment or detachment of the cleaning unit 13 is unnecessary.
Thus, the space for such a structure can be omitted.
[0105] The collected-toner box 14 includes the collection duct 13a
on one of the edges of the collected-toner box 14 in the unit width
direction. The collection duct 13a serves as a collected-toner
conveying unit for conveying the residual toner from the cleaning
unit 13 to the collected-toner box 14. The stand member 81 has the
duct cutout 81b through which the collection duct 13a penetrates.
Because of the duct cutout 81b, the residual toner can be conveyed
from the cleaning unit 13 above the intermediate transfer unit 80
to the collected-toner box 14 below the intermediate transfer unit
80 without interruption by the stand member 81.
[0106] Because the collected toner can be conveyed trough the
collection duct 13a in a direction having an angle not smaller than
450 and not larger than 900 to the horizontal plane. Thus, the
collected toner can fall into the collected-toner box 14 by
gravity. In this manner, the structure of the collection duct 13a
can be simplified.
[0107] The intermediate transfer unit 80 includes, as the
upper-unit-positioning members for positioning the intermediate
transfer unit 80 in the printer 100, the main reference portions 85
and sub reference portions 86. Hence, the accuracy with respect to
the stand members, that would other wise required, can be lowered.
For this reason, it suffices that a certain rigidity and height of
the stand members 81 be assured, and thus, the stand members 81 can
be manufactured at low cost.
[0108] Through the positioning operation, the intermediate transfer
unit 80 is inserted into the rear side of the printer body such
that the main reference portions 85 are positioned on the
main-reference-portion receiving portions 82a and the sub reference
portions 86 are positioned on the sub-reference-portion receiving
portions 83a. Accordingly, the intermediate transfer unit 80 lifts
up during the positioning, and the lower edges of the stand members
81 are not in contact with the bottom plate 101 after the
positioning. As described, the stand members 81 merely assist the
positioning of the intermediate transfer unit 80, and do not
directly position the intermediate transfer unit 80. Hence, the
positioning of the intermediate transfer unit 80 on the printer
body can be securely performed.
[0109] The stand members 81 include the exterior leaf springs 87 as
the upper-unit detachment preventing unit that prevents the
intermediate transfer unit 80 from moving in the detachment
direction when the intermediate transfer unit 80 is attached to the
printer 100. The exterior leaf springs 87 prevent the intermediate
transfer unit 80 from falling. In addition, because of the locking
unit provided to the stand members 81, the structure of the
upper-unit detachment preventing unit can be simplified.
[0110] If the stand members 81 are made of resin, the snap-fit
shapes can be provided to the stand members 81 to lock the
intermediate transfer unit 80 on the collected-toner box 14,
reducing the number of members of the printer 100.
[0111] By configuring the stand members 81 to be foldable, the
volume of the intermediate transfer unit 80 can be small upon the
transfer of the intermediate transfer unit 80. Hence, the handling
characteristics of the intermediate transfer unit 80 improve.
[0112] By configuring the stand members 81 to be detachably
attached to the intermediate-transfer-unit body 8, the volume of
the intermediate transfer unit 80 can be small upon the transfer of
the intermediate-transfer-unit body 8. Hence, the handling
characteristics of the intermediate transfer unit 80 improve.
[0113] The same advantages of the intermediate transfer unit 80 can
be realized with the transfer conveying unit 70.
[0114] According to an aspect of the present invention, the upper
unit can be prevented from being damaged.
[0115] Although the invention has been described with respect to a
specific embodiment for a complete and clear disclosure, the
appended claims are not to be thus limited but are to be construed
as embodying all modifications and alternative constructions that
may occur to one skilled in the art that fairly fall within the
basic teaching herein set forth.
* * * * *